PrincipalMatchReport can be request for any collection resources.
The resulting report identifies member resources that either represent the
requesting principal ("principal resources") or contain a specified property
that matches the requesting principal in its value. For the first match
the request body must contain a DAV:self element, for the latter a
DAV:principal-property element which in turn specifies the property to
be examined.

getPrincipalPropertyName()
Retrieve the property name that indicates which property must be search
for matching principals.
Note, that the search result must be converted to MultiStatusResponses
that must be returned back to this report.

init(DavResource resource,
ReportInfo info)
Checks if the given resource and report info are not null,
that the requested report type matches this implementation and that no
other Depth header than 0 is present.

getPrincipalPropertyName

Retrieve the property name that indicates which property must be search
for matching principals.
Note, that the search result must be converted to MultiStatusResponses
that must be returned back to this report.